Friday, February 23, 2007

Fat

Wow, I never knew how many people I would have from Fatty's site. Additionally, today I have an essay that was posted at minuscar which is more like the writings that are usually on this blog about doing with less. Today we will talk about fats and then next time we will move onto food processing and how it contributes to hunger. If you're just joining us, you can check out previous nutrition posts on Bioenergetics, Carbohydrates and Protein.I think that protein is generally over-rated, but I think fat gets a bad rap. Fats are an essential part of the diet and are extremely important. Of course there are some fats that are no good and should be avoided. Some fats are actually beneficial and have been shown to contribute to weight loss. There are three main types of fat; saturated, monounsaturated and polyunsaturated.

I think that the first thing that I need to say about fats is that gram for gram they contribute more than twice the calories as carbs or protein. They are not all that filling, so they go down easy and they add up quickly. No matter what kind of fat you consume you do have to pay attention to quantity. Vertigo, I have to clarify a little fats are the least satiating in the short term (think 15-30 minutes), but they are more satiating than simple sugars in the long run (because simple sugars will actually make you hungry after 30-45 minutes). Fats still aren't as satiating as complex carbohydrates or protein in the long run, so if you want to feel full, fats aren't a great choice.

Saturated fat is the enemy. It contributes to increased cholesterol levels, atherosclerosis, heart disease and obesity. Trans fats, although not saturated are also in this category. I'll be honest, I don't have anything nice to say about saturated fats and my mom taught me that if I don't have anything nice to say, not to say anything at all. Saturated fats are found in butter, animal products (a big part of the reason I'm sort of anti-meat), and that's really the main source. Trans-fats are not normally found in significant quantities in nature, but are found in margarine and other processed foods. I just needed to point out those things that I don't have anything nice to say about so that you too can avoid them like the plague.

MonoUnsaturated Fatty Acids... Does anyone mind if we call these MUFAs from now on? These guys are found in olive oil , avocados and nuts. MUFAs on their own are neither beneficial or harmful as it pertains to heart disease, and other major health issues. I know that you're thinking that olive oil is supposed to be the good guy and it is, but not because of the MUFA content. Remember that MUFAs aren't bad, but they are found primarily in foods that have phytochemicals and other nutrients that are extremely beneficial to the heart.

PolyUnsaturated Fatty Acids (PUFAs) are a bit more complex. They come in two primary forms, n-3 and n-6 (the n is said omega... I don't know why, some chemist made it up). n-3s are the good guys. These are the fats found in fish that are actually good for your heart. These fats actually have properties that are quite similar to Vioxx and other COX-2 inhibitors, but without the side effects. For those who care, the fats don't inhibit COX-2 like Vioxx did, but they are the building block for less sticky blood (and therefore less heart issues).

These fats also have been shown to contribute to weight loss by making your body less efficient. Normally efficiency is a good thing, but this makes your body waste energy at rest and therefore burn more calories when you aren't doing anything. (that does not make these a bad choice for athletes). Fatty fish is the best way to get your n-3s, but don't eat too much because of issues with mercury in fish. They say twice a week is how often you should eat fish, less if you are pregnant or breast feeding. You can also get n-3s from flax seed oil (and the seeds themselves to a certain extent), walnuts, almonds and canola oil (a little). n-3s from plant sources are not fully elongated and the body must complete the process before the fats are as beneficial as fats from fish. I should also mention that farmed salmon do not contain nearly the same n-3 content as wild salmon.

This is where the problem begins. n-6s compete with n-3s to be elongated. n-6s are really not a bad fat, except n-3s are MUCH better and if you eat too many n-6s they win the competition to be elongated which results in stickier blood and fewer of the benefits from n-3s. (Keep in mind that n-3s from fish are already elongated so n-6s really don't effect them.) So we need to eat fewer n-6s, where are they found? In almost everything!! n-6s are especially high in processed foods and vegetable oils. n-6s are used to extend shelf-life, so if you see products in the store that have been on the shelf, you can bet that the fat in those are either n-6s or trans fats (or they've been processed with chemicals to slow decay).

There you've got the facts, what do we do with them now? First off I want to prove that I'm at least a little bit objective by saying that wild game (animals that at one time in their lives ran, flew and ate the foods designed for them in nature) are relatively low in saturated fat and are higher in n-3s (the same type you get from fish). Most important in the fat area is getting some fish (especially salmon, tuna and other cold water fatty fishes) or wild game which don't have the same mercury issues. Wild game still has saturated fat and animal proteins which mean that you shouldn't be eating it every day.

Whether you eat your fish or not, you should also be trying to get some additional n-3s from flax seeds, and nuts while minimizing your intake of processed foods and vegetable oils (think fried food and stuff with a really long shelf life). Notice that all of the fat that you get from plant foods (except vegetable oil) is better than what you get from processed foods or animal products. That theme may be recurring in the coming posts.

Although I've gotten in trouble at Fatty's site for not being funny, I did a post on Orlistat a bit ago that I thought was funny, go check it out.

4 comments:

Anonymous
said...

Hi, got to you via FC, and it sounds like I am not the only one. In any case, I have a bunch of questions for you relative to your recent posts, and I was hoping to handle them via email. Can you send something to info AT reven.com to get started? Thanks!

I was wanting to bounce an idea off you and the blogosphere. I read an interesting "diet" in a recent cookbook by Rick Bayless. He started living this theory: most human cultures (aside from the relative affluence that Americans generally enjoy) have rather routine and boring daily meals that are moderately nutritious, and that the rich (heavy calorie) meals are reserved for special occasions (feasting). Around this theory he started eating smaller meals that were simple (salad, main dish, coffee, tea, water), and all of the creamy rich foods were reserved for family get togethers, celebrations, etc. I like the idea... and have had some success (e.g. I have weened myself off of cream and sugar in my coffee, and am down to ~8oz. a day) Your thoughts?

BTW I am also training for a charity ride in May and am trying to lose weight. And I found the Orlistat piece funny, kudos.

FC Lurker-- my wife and I made an agreement that we would only eat sweets on holidays (Holidays are defined as days where stickers are provided for my son's Highlights calender). Working together to minimize junk food has really helped us. Research has shown that taste is a learned thing. So you learned to like cream and sugar in your coffee, and now you are learning to like it without. The day will arive when cream and sugar will taste funny in your coffee because your tastes have chnaged. The same can happen for creamy, salty and sweet foods. I've noticed that the Olive Garden is less of a treat for me because it's all really salty and rich compared to what I"m used to.

I'm a registered dietitian, and a triathlete, but my masters program didn't leave much room for ex. phys. type stuff in the coursework (which I was really interested in). I have a few questions about electrolyte replacement during long events, which has been a problem for me. Email me at mountainmann42@hotmail.comthanks and congrats on the PhD!